docs: def limiter(self, gain=3.0):
          """limiter takes one parameter: gain in dB.
  
          Beware of adding too much gain, as it can cause audible
          distortion. See the compand effect for a more capable limiter.
          """
          self.command.append('gain')
          self.command.append('-l')
          self.command.append(gain)
          return self